ORONO, Maine (AP) — Lobsters aren’t just for eating anymore.

The shells from Maine’s signature seafood are being used to manufacture decorative tiles, trivets and drinking-glass coasters. Work is under way to utilize them in countertops and tabletops. And at the University of Maine, a professor has developed prototypes of biodegradable golf balls and plant pots made out of ground-up lobster shells.

“Instead of dumping the shells at landfills, the idea is to add value to the product, which hopefully will funnel back into the industry,” said David Neivandt, a professor of chemical and biological engineering who created a biodegradable golf ball with a core made of lobster shells.

Lobster processors dispose of tons of lobster shells that are left over after the meat is removed. Industry leaders have long wondered if there might be a way to make money from the part thrown away.

Neivandt and one of his students, Alex Caddell, together developed a golf ball using ground-up lobster shells mixed with a glue-like substance for its core. The shell is also made out of naturally derived biodegradable material, but they aren’t giving specifics because they don’t want to give away any secrets. The ball is the same size and weight as a standard golf ball but is intended for use on cruise ships or at driving ranges that are on lakes or the ocean.

Dumping golf balls into the sea is prohibited under international convention because they are made of plastic and don’t break down, but the lobster golf ball is biodegradable and disintegrates in the water in about three weeks.

Caddell, who played golf in high school, said he and Neivandt tested numerous balls that cracked, didn’t fly quite right or otherwise didn’t make the cut. Finally, they came upon just the right mixture that makes the ball hit nearly like the real thing.

“The first time I hit it, I was surprised it didn’t shatter into a million pieces,” Caddell said. “And it flew straight. I usually have a pretty bad slice, so to hit it straight was amazing.”

With an iron, the ball flies nearly the same distance as a standard ball. With a driver, it’ll go 60 to 70 percent of the distance.

There are other biodegradable golf balls on the market, which sell for about $1 each, Neivandt said. The raw materials for the lobster golf ball cost about 19 cents per ball, which could make it competitive in the open market.

The university has filed a provisional patent for the lobster-shell mixture. Neivandt said a private company could buy the licensing rights and market the ball, or the school could spin off a company that would produce it.

While developing the golf ball, they also came up with a plant pot made out of lobster shell mixture — which has a high calcium content beneficial to flowers and vegetables — to place directly in the ground with flowers or vegetable plants.

Turning seafood waste products — such as lobster or clam shells — into products with commercial value would benefit the seafood industry, said Bob Bayer, head of The Lobster Institute Research and Education organization at the University of Maine.

Most lobster shells are dumped in the garbage or at landfills, Bayer said, with some of it going toward seafood compost used for gardens or turned into lobster meal, which is an animal feed additive. There have been failed efforts to turn the shells into other marketable products — such as lobster bait — over the years, so Bayer is pleased to see new products come on line.

“The whole idea is to add value to our lobster,” he said. “The more value we can extract, the more fishermen will be paid and more jobs will be created.”

EcoSeaTile LLC, a small company based in Mount Desert, for the past year has been making tiles of reclaimed lobster, mussel, clam, oyster and scallop shells for use in homes and businesses, selling at dozens of high-end tile shops in New England and New York. It recently added a line of drinking-glass coasters that are sold at gift shops.

Owner Mickey Shattow said the tiles seem to be most popular among customers who live on or near the ocean.

“This probably won’t be a big hit in Chicago, but I can see it being a hit up and down the coast,” he said. “But the coaster might be a hit universally.”

Aron Buterbaugh is making trivets in the shape of lobster claws, made of lobster shells and recycled glass, among the products at his Beachstone, Inc., a company he runs out of South Portland.

He’s also working on developing vanities, bathroom countertops, tile accessories and tabletops for patio furniture, coffee tables for the home and restaurant dining room tables that utilize shells from mussels, clams, oysters, scallops and lobsters in combination with recycled glass, he said.

“They’re plentiful. They’re a waste product. They’re decorative,” he said. “It’s a win-win-win strategy in my opinion.”